Electric switchgear



' Aug. 23, 1938. J. LlNDE 2,128,149

ELECTRIC SWITCHGEAR Filed Dec. l2, 1936 rverwtof: Leoryarcl J'. Linde,

bywaI/H Patented Aug. 23, 1938 ELECTRIC SWITCHGEAB.

Leonard J. Linde, Drexel Hill, Pa., assigner to General Electric Company, a corporation of New York Application December 12, 1936, Serial No. 115,643

, 5 Claims.

My invention relates to electric switchgear of the draw-out type, more particularly to meansY The application of circuit breaker units, such as heavy duty air circuit breakers, for example, to draw-out type swltchgear necessitates a relatively compact design since these units are often used where space is a very important factor, such as in underground substations, for exampler `In such installations it is highly desirable that the switchgear units occupy minimum space-when in normal operation, but that compactness in design is not accomplished at the sacrifice of accessibility to the switchgear unit when it is withdrawn to the disconnected position, or at the expense of the emciency of the draw-out mechanism.

In accordance with my invention, compactness in design is accomplished without sacrificing any of the more desirable features by providing a collapsible extensible guide for the circuit breaker unit and by operating the draw-out mechanism in a direction generally parallel to the base panel of the circuit breaker unit, i. e., transverse to the movement of the breaker unit. Accordingly, the lateral space required for the draw-out mechanism exceeds at no time during the operation thereof that required for the minimum dimensions of the mechanism. y

My invention will be more fully set forth in the following description referring to the accompanying drawing, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

Referring to the drawing, Fig. l is an elevational view partlyfin section of draw-out type switchgear in the/ connected position embodying the present invention, and Fig. 2 is a similar view showing the switchgear unit in the disconnected position.

The draw-out switchgear shown by Fig. 1 comprises stationary circuit terminals generally indicated at I and 2 mounted on a vertical supporting panel 3. A circuit-breaker unit 4 which is provided with terminals indicated at 5 and 6 is relatively movable with respect to the fixed terminals between connected and disconnected posi- (Cl. F15-298) tions and is supported and guided for horizontal reciprocal movement by means of a pair of horizontal guide rails 1 between which the unit 4 is positioned, and rollers 8 mounted onvthe unit 4. The circuit breaker unit 4 includes a power interrupting breaker, such as a heavy duty magnetic-blow-out air circuit breaker, for example, and is normally closed when the unit is connected as shown by Fig. -1`. Prior to disconnection of the unit at the stationary terminals the circuit breaker is opened in accordance with well-known practice. The details on the circuit breaker are not shown since the breaker per se forms no part of the present invention and a detailed description thereof is unnecessary for a complete understanding of the invention.

The disconnecting devices for connecting the breaker unit 4 to the terminals I and 2 are generally indicated at 9 and I0 respectively, and as shown are of the plug and socket type. As best illustrated by Fig. 2 which shows the disconnecting contacts in the open circuit position, the breaker terminal contacts at 5' and 6' engage coacting socket contact members I' and 2' which are connected to the terminals I and 2 respectively. The disconnect contacts per se are described in detail and claimed in my copending application for Electric disconnecting devices, Serial No. 115,642, filed concurrently herewith and assigned to the same assignee as the present invention.

When the circuit breaker is in the connected position as shown by Fig. l, it is supported by the rollers 8 and by the guide rails 1 at opposite sides o f the unit, the rails 1 supporting the unit in cantilever fashion and being braced with respect to the panel 3 as at 1. When the breaker is rolled to its disconnected position as shown by Fig. 2 it is supported at each side by `a collapsible extension II of the guide rail, which is manually extended to the position shown prior to the disconnecting operation. The extension II is also supported in cantilever fashion at the end of the rail 1 by pins I2 secured to said rail.

When the unitv 4 is rolled inward toward the connected position, the extension II .is rotated manually about the pins I2 and slides downward to the collapsed position shown by Fig. l wherein it is held by a pin II' secured to the extension and engaging the guidenraill. For the purpose of suitably guiding the extensions II, each guide rail is bifurcated as illustrated.

The draw-out mechanism comprises essentially a vertically movable cam member or plate I3 at each side of the unit, each cani member being mounted on and vertically guided with respect to the panel 8 as by pin and slot connections indicated at Il. Vertical reciprocal movement of each member Il is effected by a pinion gear Il enacting with a rack il forming a part of the cam member and an operating crank il for rotating the pinion gear. The operating crank I`| operates through a common shaft both cam members Il for simultaneously operating the same.

The cam connections between the member. Il

v and the unit I include a pair of inclined slots at I I formed in each cam member opposite the breaker unit adapted to receive rollers I9 which are carried by rearwardly extending lugs 2l secured to the base panel of the circuit breaker unit. The slots are so arranged with respect to the rollers that when the rollers are in the lower parts of the slots as in the breaker connected pomtion illustrated by Fig. l, lowering of the cam member II is effective to force the breaker unit 4 towards the right and out of engagement with the disconnecting contacts. After the contact engagement is broken. the unit I is free to be rolled to the disconnected position illustrated by Fig. 2 where it is readily available for inspection or re- Dill'.

The connecting operation is perfumed by rolling the unit l to the point where the rollers Il enter the slots Il, after which the cam member Il is racked upward to force the disconnect contacts into complete engagement. Since the unit 4 is acted upon by the draw-in force at four points on its base panel, the unit is forced into its operative position evenly and smoothly and without binding.

It will be noted that the lateral space required by the draw-out mechanism need be not greater than the width of the cam member itself. This is particularly important in certain types of aircircuit breakers, for example, wherein the maximum dimensions are in the vertical as contrasted with the horizontal or draw-out direction. In order to maintain the total space factor as low as possible, it is therefore highly desirable to limit the maximum horizontal dimensions. 'I'his is not readily done with conventional drawout mechanisms.

It should be understood that my invention is not limited to specific details of construction and arrangement thereof herein illustrated, and that changes and modiiications may occur to one skilled in the art without departing from the spirit of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Electric switchgear of the draw-out type comprising electric circuit terminals, a circuitinterrupting unit relatively movable with respect thereto, and means for effecting bodily movement o! said unit relative to said terminals including a cam member movable transversely of the direction of movement of said unit and along a substantially longitudinal path, said cam member having comparatively limited dimensions with respect to said direction of movement for insuring compactness of said switchgear. Y

2. Electric switchgear of the draw-out type comprising a stationary panel. electric circuit terminals mounted in spaced relation on said panel. a circuit-interrupting unit movable with respect to said terminals in a direction generally at right angles to said panel. and means for eilecting bodily movement of said unit relative to said terminals including a cam member mounted on said panel in close proximity thereto and guided for longitudinal reciprocal movement only in a direction transverse to the direction of movement of said unit.

3. Electric switchgear of the draw-out type comprising a stationary panel, electric circuit terminals mounted in spaced relation on said panel. a circuit interrupting unit movable with respect to said terminals in a direction generally at right angles to said panel, and means for moving said unit toward and away from said terminals including a cammember guided for longitudinal reciprocal movement only in a direction transverse to the direction of movement of said unit, said cam member mounted on one part of said switchgear in closeproximity thereto, rollers coacting with said cam member mounted on another part of said switchgear and gear structure for eiiecting reciprocal movement of said cam member.

4. Electric switchgear of the draw-out type comprising stationary circuit terminals, a circuitinterrupting unit guided for longitudinal reciprocal movement with respect thereto, and means for effecting bodily movement of said unit relative to said terminals comprising a cam member guided for longitudinal reciprocal movement in a direction transverse to the direction oi' movement of said unit, said cam member having cam faces inclined with respect to both directions of movement of said cam member and circuit-interrupting unit respectively, and means mounted on said unit for coacting with said cam faces arranged so that longitudinal movement of said cam member is eectlve to torce said unit into connected or disconnected position;

5. Electric switchgear of the draw-out type comprising a vertically pomtioned panel, electric circuit terminals mounted in spaced vertical alinement on said panel, a circuit-interrupting lunit guided for horizontal reciprocal movement v with-respect to said terminals. and means for eilecting'bodily reciprocal movement of the unit between connected and disconnected podtions including a pair of cam plates mounted on said panel and guided for vertical reciprocal movement, said cam plates being laterally spaced on said panel for coasting with opposite sides ot said unit, each ot said cam plates having a plurality of slots opening towards said unit and inclined with respect to the directions of movement of both said cam member and unit, a plurality of rollers carried by said unit at the rear side thereof i'or coasting respectively with said slots, and means for edecting simultaneous vertical reciprocal movement of said'cam plates for applying at said rollers a force for uniformly moving said unit either to its connected or disconnected position with respect to said terminals.

LEONARD J. LINDE. 

